To what degree is violet light magnetified to change into UV heat radiation?
First of all, magnetified is not a word, so I can only assume you mean “transformed.” Electromagnetic radiation is sometimes transformed from shorter to longer wavelengths through processes such as fluorescence or phosphorescence. This type of transformation would convert violet light to something like green or orange light, but not to the shorter-wavelength ultraviolet. It would be very rare indeed, but not completely impossible, for radiation to be converted to shorter wavelengths (which are higher-energy photons). Secondly, heat radiation is normally considered to be infrared radiation (longer wavelengths than visible) and not ultraviolet. It is true that absorption of ultraviolet radiation (or any energy) can raise the temperature of an object, but this temperature change itself is not considered heat radiation (the object might then emit some infrared energy, depending on its new temperature).
